Collision rates in near-resonant optical lattices

We present a simple method for calculating the binary collision rate between atoms in near-resonant optical lattices. The method is based on Monte Carlo wave-function simulations, and the collision rate is obtained by monitoring the quantum flux beyond the average distance between the atoms. To illustrate the usefulness of the method, we calculate the collision rates for a wide range of occupation densities and various modulation depths of the lattice. The method presented here, combined with the semiclassical calculations accounting for intrawell collisions, can simplify the study of the effects of binary collisions on the dynamics of atomic clouds trapped in near-resonant optical lattices